Electro-mechanical actuator



Jan. 8, 1957 M. 1.. NELSON ET Al. 2,776,570

ELECTRO-MECHANICAL ACTUATOR 2 Sheets-Sheet 1 Filed June 22, 1954 N/HHHN at mi Hmw 1N VEN TOR. Ill/JETl/VL NELSON BY CARL JKOPF HZJ/VS UH/ERMSTAD M 6%,Mg/W

Jan. 8, 1957 M. L. NELSON ET Al. 7

ELECTRO-MECHANICAL ACTUATOR 2 Sheets-Sheet 2 Filed June 22, 1954 mu lll w m l iu INVENTORS MdRTl/V L. 11m 50m y 04/?1. J KUPP Jam/vs a HJERMSTAD United States Patent 2,77 6 57 ELECTRO-IWECHANTCAL ACTUATOR Martin L. Nelson, Park Ridge, Carl J. Kopp, Arlington Heights, and Hans U. I-ijermstad, Chicago, 111., assignors to Electra-Seal Corporation, Des Plaines, Ill., a corporation of Illinois Application June 22, 1954, Serial No. 438,524

21 Claims. (Cl. 74-2) closed in the Schwartz et al. Patent No. 2,535,095, granted December 26, 19 50. In the prior art devices for controlling the release of bomb suspension equipment in aircraft, or the like, a spring loaded member has been held in a cocked or latched position by means of ball members that are movable between latched and unlatched positions. In the operation of the prior mechanisms, a solenoid is energized to control the ball members to move them from the latched position to the unlatched position in order to release a spring loaded ram. The spring loaded ram upon being unlatched by the ball members will, under its own spring tension, be moved to a position to the unlocked or uncocked position. Also, the prior art devicesof the type noted above are provided with electrical transfer switch mechanisms whereby the circuit initially completed for energizing the solenoid of the first bomb release mechanism of the first station will be transferred to the next bomb release stationafter the electrical impulse for controlling the release of the first bomb release station has been interrupted. 1

It has been found that the prior art mechanisms, in-

cluding the mechanism disclosed in the above mentioned Schwartz et al. patent, will not withstand the usual vi-. bration and shock tests to which such mechanisms are subjected in order to meet military requirements. The extreme vibration and shock conditions to which these devices are susceptible, for example, created during acceleration of high speed aircraft, and the like, may cause inadvertent release of the bomb release mechanism.

Furthermore, vibration and shock conditions that are insufiicient to cause inadvertent release of the prior mechanisms may in some instances nevertheless cause accidental closing of the transfer switch contacts in the electrical circuit, thereby inadvertently causing the completion of the circuit for releasing the succeeding bomb.

Furthermore, when the prior bomb release mechanismshave been tested to determine whether or notthey will withstand severe shocks and vibrations, many of them have been rendered completely inoperative. I For example, when a mechanism of the general type disclosed in the Schwartz et al. patent was given the usual vibration and shock tests, the ball members of the latching and unlatching mechanism badly scored and distorted the ball channels or guides in which they function to control the latching and unlatching operation of the bomb release mechanism. Thus, the mechanism was damaged to such an extent that it was either held in a latched position which prevented its normal release or it inadvertently released from its latched position.

It is the principal object of the present invention to provide an improved mechanism of the type described above in which the ball like members for controlling the ice latching and unlatching of the mechanism are entirely eliminated.

It is a further object of the invention to provide a mechanism of the type noted which is exceedingly small and compact in size and light in weight, while still providing a tremendous amount of energy or force to actuate the bomb shackle release mechanism as soon as it is released from its latched position.

.It is a further object of the invention to. provide a mechanism of the type noted that substantially eliminates the possibility of failure and inadvertent release when tested by the usual shock and vibration test devices.

It is a further object of they invention to provide in the mechanism of the type noted, a release device that will unlatch the cocked plunger of the mechanism in response to a predetermined movement of the release device and to utilize the movement of the plunger from a cooked position to an uncooked position to govern additional movement of the release device.

It is still another object of the present invention to provide in a mechanism of the type noted, means for actuating the mechanism from its latched position to its unlatched position either electrically or manually so that in response to the failure of the electrical system, the mechanism may be manually controlled.

Other objects and advantages of the invention will best be understood by reference to the following specification taken in connection with the accompanying drawings in which:

Fig. 1 is a perspective view of the present invention mounted in place upon a conventional bomb release shackle;

Fig. 2 is an enlarged longitudinal cross-sectional view of the present invention shown in its cocked or latched position;

Fig. 3 is a sectional view taken along line 3-3 of Fig. 2;

Fig. 4 is a fragmentary sectional view taken along line 4-4 of Fig. 2;

Fig. 5 is a sectional view taken along line 55 of Fig. 2;

Fig. 6 is a right end view of the mechanism of the present invention shown in Fig. 2; and

Fig. 7 is a schematic wiring diagram showing the manner in which the electrical circuits are completed for sequentially controlling a plurality of mechanisms in accordance with the present invention and includes the circuits for the signal lamps to indicate the cocked or latched and the uncooked or unlatched positions of each mechanism.

Referring now to the drawings, wherein like reference characters have been utilized to designate like or corresponding parts throughout the several figures, there is shown in Fig. 1 a conventional bomb release shackle 10 having a release lever 11 and a plurality of bomb supporting hooks 12. The release mechanism 15 of the present invention is shown mounted upon the top surface of the frame of the shackle 10. This mechanism is shown in the remaining figures of the drawing except for the supporting bracket 14 which is secured to the release mechanism 15 and is provided with a spring tensioned manually operable release button 14a which, when pulled outwardly toward the stop 14b will permit the release mechanism 15 to be withdrawn from the bomb release shackle 10.

Referring now to Fig. 2 of the drawings, it will be seen that the release mechanism 15 of applicants invention comprises a substantially cylindrical housing 16 having integrally formed therewith, an upstanding housing portion 17 for enclosing a transfer switch mechanism 76 which is demountably supported therein in the manner essary, dueto the extremeshock that occurs-as-aresult of the release of the spring loaded plunger of the mechanism, to fabricate the housing 16 from stainless steel or; similar hard dura'ble material; However in accord-"- ance with the present invention, the amount of shocle'that is' transmitted to the housing 16 is reduced to' aminimum so that the housing lo isprefcrably made-from aluminum or. other light metals in order to further reduce the total weight of themechanism. f A plunger 18 is slidab'lelongitudinally 1 in 1 the cylindrical housing 16 and is integrallyvformedwithsan inner sleeve 19. and an outer: sleeve 20.1 The.- outer sleeve 20 is providedg-"at l its right end as seen inih igga 2, we: am enlargedaring-like member 21 having an'zangularscircum' ferential stopi surface '22; Between the inner I and outera heavy-compression spring 2.3;t'wliich; in- -t'he latohed or-cocked position of-the1meclranism, .is compressed and tends to force the-v plunger 18 :outwardly; to the :l'eft as} seen 'in-EigJ-Z atithe instant ithatthe rncchanism nnlatched; in order-to drive theplun ger 'outwardly until the angular circumferential-stop surface -2-2izoni the -ring 2 1 engages the? stop ring 24; Preferably; the spring 23 shouldbe of sufiicient size to exert arelativelyhigh pres- 1 against the outer shoulder 26 on the casing 16. At" the end-of the ou-twa'rd travel,- the angular circumferential cam 40 which is secured to the shaft 41 in any desired manner,- for example, by means of a-splitspring-washer 42 secured in the slot in the end of the shaft. In order to prevent rotation of the cam 40 wit-h respect to the shaft 41 the cam may be keyed to the shaft.

By referring to Fig. 5, it will be seen that the cam 40 includes the opposite flat surfaces 43 and 44 which are arranged to'cooperate with the v angular cam follower surfaces 45"and"4'6provided on the respec-tive latch memstopsurfa'ce 22' on 'the outer sleeve '01': the plunger-18 The mechanism also in'cIude's -a stator or magnetic core:

27' which is provided at-its-o'uter right end, -as*best-fseen"- in Fig.r3; with pole pieces 28a;-2-8b,28c and 28d and'{ acent-ral pole piece 29% The central pole' piece 2 9 of the magnetic core 27 is the magneti-c core for the solenoid5303 the left end: as seen in Fig. 2, the core is provided: with oppositely disposed slots' 32 to' receive the catch or? latch members 33 and 34'. Eachof v the latchf members 33 and; 34 are provided with lugs 35 and 3'6 respectivelyiin-order to-retain-jthe-latchspring'37 in on tion'between the-respectivelatches 33 and 34. The Iazeh spring: 37 i's a compression spring and is arranged to nor mally' hold the-latch members 33 and- 34'in -aseparated;

positiom Inasmuch as the latchfme'mbers are each providedawith the angular surface 38 that c-ooperatewith corresponding surfaceson the-inner wall'of the plunger themanncrto be describe'd hereihaften 18; the plunger will be retained-in its latched posit-ionuntilsthe --spri-ng 37 is permitted-to be-compressedfin- The latch members 33 and 34 are pivotally mounted bythe pivot pins 39, at'jtheir rightends in the -slots 32 provided in themagnetic core 27. Thus, the-puter or;-

q t the Piv pin;

In order to. hold. the latch. members in the expandedi; position illustrated. in the drawing, there is provideda.;

left ends ;of the latch, members 33jandy34 maymivot;

ti'on illustrated-in Fig; 5; the cam willhold thespacedapart latch members 33 ahd34 in1the expanded positions to prevent them from compressing to release the core 18?.frorn its; illustrated latched; positions. If the shaft 41 is rotated in a clockwise direction as seen in Fig.5 a short distance; the fiat'canr surfaces 43 and 44 will then cooperate respectively with the cam follower surfaces 45 and 46 respectively provided on the latch members 33 r and 34. When this occurs, the heavy spring 23will be effective to'begin to move the plunger 18 out-'- wardly to-the left 'as seen-in Fig; Zagainst the angular surfaces. 38 provided on-the respective latches. This will cause the latch members to r be moved toward each other against the tension of the spring 37 and-due to the excessive force exerted by the heavy spring 23 in moving the plunger- 18 outwardly, the cam follower ur faces 45 and 46 will be compressed against the-cam surfaces43 and 44 to' such an extent that it will cause further rotation of. the-cam 40 and-the shaft 41.

ln-order to retain the shaft 41 in a position that will permit the cam 40 =to cooperate with the latch members 33'--'and 34; a stop-nut"47- is provided which is threadedupon -the shaft -41 and-cooperates with the correspondingedge-'surfaces-onthe core-27 to retain the shaft 41- in oscillatory positionin the. core; At this point, it should be notcd that-a central opening 48 i-s-provided in the core 27 so that-the shaft 41 may be inserted thereth-rough.. However, thecentral' opening 4-8 is somewhat oval in shape-inorder to perm-it"the shaft'to-seek its-own center between the respective latch members 33 and 34 whether thecaIn40- is in the position illustrated in Figs. Z-and 5 or whether it has'been-rotatedto unlat-ch the latch members 33 and 34. Since the central opening 48' is oval shaped; it will prevent theshaft 41 from binding therein if it is moved= vertically during the actuation of the;

device.

'Inorder to'prevent relative rotation betweehthecore 27-havingjthe central pole piece 29 on the core 27 and 'the 'externa'lpole pieces 28a to 28d; inclusive, and the inner wall of -the-cylindrical housing 16, the'core- 27and= thehousing=16;-are respectively provided with cooperating longitudinal keyways 49- which are located" along the lower rear or right-hand portion of the respective elements' as=seen-in Fig. 2 and as more-clearlyshown-'in'the lower portion ofF-igi 3'.

A "1otor 5fihaving" four circumferentially spaced-apart" polkpieces -Sla to 51a; inclusive; is keyed to or=rigidly secured in any desired{ manner to the shaft 4las seen in- Figl' to cooperate with the central pole piece 29 andthc respective circumferentiallyspaced-apart pole pieces 28a to:2 8d inclusive 'ofthe" magnetic core 27. Inordcr toprjovide-more-efiicient magnetic flux paths between the respective pole pieces of the rotor 50' andtheresp'ective" pole-pieees-of thecore 27; eachof the-pole piecesSla and- 5 1 c is arranged so that a portion ofthe leading; edgesthereof will over-lap or extend beyond the. cooperating surfaces of the stationary pole pieces 23a and28'c, as

bestshown in Fig. 3 Thus -when thesolenoidBil-is one-r rection, asseen. in Fig. 3, untilthe extensions or stops 52 b an d;-52d respectively engagev the corresponding.sta .v tionary pole :pieces 28 b and 28d. Thus, the. magnetic flux created by the energization of the solenoid 30 will first rotate the rotor 50 in the clockwise direction as described above and it will then magnetically hold the rotor 50 in 7 its advanced rotary position by means of the stops 52b and 52d in engagement with the pole pieces 28b and 28d as long as the solenoid 30 remains in an energized condition. 7

In addition to the foregoing, the rotor 50 is provided with oppositely disposed lugs 53b and 53d which extend upwardly as viewed in Fig. 3 and which extend rearwardly as seen in Fig. 2. In the present invention, only the lug 53d is effective during the rotary movement of the rotor 50 in a clockwise direction as seen in Fig. 3 to cooperate with a switch keeper 54 to prevent release thereof, as will be described hereinafter, whereas the oppositely disposed lug 53b is provided to maintain the balance of the rotor 50 and to cooperate with the stop on the spool head of the coil spool 31 to limit the rotary movement of the rotor 50 in a counter-clockwise direction, as seen in Fig. 3, to the illustrated normal position.

In order to provide a bearing for theshaft 41 of the rotor 50, the right-hand end of the magnetic core 27 as seen in Fig. 2, contains a radial and thrust bearing 27:: into which the shaft 41 is inserted. The face of the shoulder on the rotor 50 engages the cooperating end face of the thrust bearing 27a to prevent axial movement of the shaft 41. As seen in Fig. 3 the end of the central pole piece 29 of the magnetic core 27 extends in a complete circle and the cooperating circular slot formed in thesurface of the rotor St) is arranged so that the rotor 50 may rotate its associated shaft 41 with respect to the central pole piece 29. The manufacturing tolerances between the pole piece 29 and the cooperating annular slot in the rotor 50 are such that the rotor may freely rotate.

As previously noted, the solenoid coil 30 is wound on the coil spool 31 and the latter spool is arranged so that it will slide over the end of the central polejpiece 29 of the magnetic core 27 to assume the position illustrated in Fig. 2. The coil spool 31 is preferably made from nylon but it may be manufactured from any other type insulating material. At this point it may be well to note that the switch keeper 54 illustrated in Figs. 2 and 3 extends upwardly fro-m the central pole piece 29 to the transfer switch 76 to be described hereinafter, and parallel to the corresponding spool head of the coil spool 31. In order to permit the switch keeper 54 to be movable vertically as seen in Figs. 2 and 3, either away from or toward the central pole piece 29 andto retain the keeper 54 inthe proper position, the right-hand spool head of the coil spool 31, as seen in Fig. 2, is slotted from the junction of the central pole piece 29 to its outer peripheral edge. This slot retains the keeper 54 in its allotted position during vertical movement therein.

Adiacent the keeper 54 there is provided a nylon washer 55 which is placed around the central pole piece 29 adjacent the outer right-hand surface of the spool head on the coil spool 31 and it is held in place by means of the retaining ring 56. The last-mentioned retaining ring is of the type that may be circumferentially expanded and when released will compress itself into a cooperating slot in the central pole piece 29 to lock the nylon washer55 and the coil spool 31 and the solenoid coil 30 wound thereon in position.

Referring now to Fig. 3, it will be noted that a C- shaped spring 57 is removably secured at one end in a cooperating openingin the rotor 50 and at the other end it is removably secured in the end of the' pole piece 281). This spring is under tension 50' that when the rotor 50 is rotated in a clockwise direction, as seen in Fig. 3, the spring while lightly resisting such rotation, is not strong enough to prevent the stops 52b and 52d thereon from engaging the cooperating pole pieces 28b and 28d. As soon as the magnetic flux dies down between the pole pieces of the rotor 50 and the cooperating stator pole pieces, the spring 57 becomes effective to restore the that causes the rotor 50 and its cooperating shaft 41 to be rotated in the clockwise direction as seen in Fig. 3. It is an additional feature of the present invention to manually control the rotary action of the rotor 50 to unlatch the mechanism.

Before describing the manual control of the release or unlatching of the mechanism, the manner in which the parts are assembled will first be discussed. The cylindrical housing 16 first receives the felt ring 25 which is placed in the groove 24a and then receives the split stop ring 24 which is held compressed in diameter. When the ring 24'is in a position to be expanded into the groove 2411, the compressed ring is released so that it may expand outwardly and set itself in the groove 24a.

Before the stator or magnetic core 27 is inserted into the central opening formed by the inner sleeve 19 on the plunger 18, the various parts supported by the core 27 must first be assembled together. Thus, the solenoid coil 30 wound upon the coil spool 31 is placed in the position shown upon the right-hand end of the core 27 with the nylon ring 55 and the retaining ring 56 holding the same in place by placing the latter ring in the cooperating slot in the circumferential well of the central pole piece 29 on the core 27. Thus, the solenoid 30 and the coil spool 31 are now held in position on the core 27. Thereafter, the rotor 50 is secured to the right end of the shaft 41, inany desired manner, and the shaft is inserted through the bearing 27a and the central opening 48 in the core so that'the left end of the shaft extends beyond the left end of the central core 27. The stop nut 47 is now threaded upon the corresponding threads on the shaft 41 to hold the shaft 41 with its rotor 50 in cooperating relationship with the central pole piece 29 on the core 27. It should be understood, however, that the central pole piece and the circumferential groove formed in one end of the rotor 50 closely cooperate to providean efiicient magnetic flux path therebetween. After the stop nut 47 has been secured in the manner described above, the cam 4t will be placed upon the shaft 41 and keyed in place in a well known manner to prevent relative rotation between the shaft 41 and the cam 40. In order to prevent the cam 40 from sliding longitudinally along the shaft 41, it is retained in place by means of the split spring washer 42 which fits into a cooperating groove formed adjacent the left end of the shaft 41.

As previously described, the core 27 is provided with slots 32 in the upper and lower circumferential surfaces as best seen in Figs. 2 and 5 to respectively receive the pivot pins 39 integrally formed on the latch or catch members 33 and 34 and function to providethe pivot point about which the latch members 33 and 34 may pivot at their outer ends toward and away from one another. In order to retain the latch members in expanded position away from one another, the latch spring 37 is placed on the lugs 35 and 36 provided respectively on the two latch members 33 and 34.

After the above described parts have been assembled in the manner described, the main compression spring 23 is placed on the core 27. The rotor 50 is then turned to its trip position so that the cam 40 will be rotated sufficiently to permit the latches 33 and 34 to bepressed toward each other, by means of a tool or the like, as the core 27 and the spring 23 are inserted into the central opening formed by the inner sleeve '19 on the plunger 18. The spring 23 will be inserted into the annular'opening formed in the plunger 18 between the inner sleeve 19 mide-c ter sle vezm whenithen sea s; iQFQQ;

tion to hold the plunger 18 in its loaded or cockedrposii-v tion. Thereafter, the return spring;;; 57- fon'therotor is assembled; in place, issbest illustrated in retainithexotor; S O-in-its, latchedror, CQCkBd;pQS1tlQH. I

Thexplunger; 18+ is-;n,o,w in conditiontqbeinserted in place-v in the cylindrical housing' lfi. Consequently, the plunger 1'8tupon'being inserted in thetcylindrical housing 16i-will beyin theaposition shown in Big. 2. Inorder-toi hold the plunger 18 and the cylindrioaL-housing 16inas1- sembled position," the spliti rin ,W-asher 58 zisinserted into the-groove-Stla, formed-instheinnerwallof the cylindrical housing- 16- and is themexpanded sothatiitwill seat itself therein to. preventthetwithdrawal o flthe co l-e27 and. the;plung er 18 from the: cylindrical. housing 16.t

In order to'proyidethe manualcontrol for the-rotor 50;,- a rtripwmember 59 is rotatably mounted in a trip hous ing 60 with a C-shaped spring 6 1? having, ltS,-DdS-1'Spe C,-f tively secured in the trip-member;59y'and;the triphousing 60: It should; be understood,- however,- that; openings are-providedinthe, trip member 59and the-trip housing- 60. to; dismountablyreceive the: respective; ends of-- they C-ishaped: spring 61. The spring; is -.tensioned' so that it will normally tend. to. rotate; the; trip, member 59 -in -a as antinte relun t ia io b v s rted nvi he i ht:-

hand; pen endof the cylindrical housing 6Huntil the,

y.. shoulders, 70,011, the trip housing 60 engages P r p. the-split ringwasher58L Thereafter, the sealing ring'71, is :p1a1. .wund;t e t ighnu ing. 0. gain t he. per phe a should r. 70 t e eon. an -is. hc1d,. n..p c. y th -Wei cumferential washer 72; The trip housing 60, the sealing,

ring 71 ar1 d washer 72 ar e then securedin place bymea ns ofjthe retaining ring 73' which isof the typethat can be omn essed ufii i tly, 9 n e t e sa e in he and opening in the housing 16 and then released so that it will cooperatewith -theslot 74 formedon the inner wall the s li d sa ih s n jl djace t the here It shouldbe understood that the retainingring 73 is nor- ..mally ten i ne to pan twa i t 4 i to retain the trip hous ing andthe assembled partsltherecounterclockwise.direction,,-as seeniin Fig. 4:so that the shoulders; formed inwthettripmemlber 59 are: adjacent the; oppositely disposed studs 62; on;the--outer-surface of the;

rotor The-trip-member 59 although tensionediby the;

spring161; in.-a counterclockwise direction as seen in Fig, 4 remains -in the position;illustrated-because the trip arm 65. andthe .pins; 66-wthereinare normally.,inqlengagement -j withzonexend 1 of: the-slots- 67; provided; in the outer :surfaceoft-the; trip. housing '60:- a

The: trip, member S9'is rotatabiy mounted in -the trip.

housing; fiti withthe washer 63-and thesealing ring 64 therebetween, asaseen in Figs-2'. The; shoulder 68 on pins 66 are inserted into oppositely disposed openings providedin the trip arm 65 and extend sufiiciently. be. yond the rear surfacethereof tocooperate. with the slots 1 67 in the outer surface of the trip housing, 60. These slots form the stop for the pins 66 and are circumferentially arranged in; the outer surface of the trip; housing fl.:SQth,Qti thC pins 6o-normally'engage oner'endof: theslots under controlof the counter-clockwise tension of. V lhtI-@:$llqdt spring; 61: on; the triprnemher: a' ras, viewed ill-Big, 4. The -slots :67 extend circun ferentially. inthe; outer surface. of thetripvhousing a predetermined dis; tance so. thatthe trip arm: 65, by meansrof thepins 66, ca-nqbe rotated. ina. counter-clockwise direction as seen a in. Fig; 2,. and in 'aclockwise direction as seen'in Fig.4 to, rotate the-trip membervwith the, shoulders thereof in, engagement with the studs 62 on the .outer surface of the. rotor 5.0..tosimulate. the action, of the rotor under controlwof the magnetic. flux generated byzthe solenoid 301,011 the coil spool 31., Asso'onasv themanualrotetion of the trip 21111165,. is terminated and it isreleased, the Csshaped spring 61 will restore, the trip 1nernberv59 in a connterrelockwise direction tovthe. position illustrated in:

Theiabove assembly Comprising; the tripmember 59;,

the stripe. housing, 6Q,-lthe spring 61,, the Washer .53,v the sealing ring 64,,the-trip, arrn; and itsgassernbledrpinsi;

on in cooperating relationship with the studs ol on the outer surfaceof the rotor. 50.

It will vbe appreciated from the description thus far that all of the parts comprsing the mechanism of the "giving; a detailed description of the operation of the mechanism-of-thepresent invention the manner in which the transfen switch '76"is mounted thereon will now be described I As previous-ly described the cylindrical housing 16 is integrally formed with an upstanding transfer-switch hously-assembled unit and comprises two .parallel upstanding longitudinal plates 77aand 77b; preferably-of"insulating material; each having six electrical contacts 78a to 78f, inclusive; secured thereto in any desired manner. The plates 7 '7it and-77b are respectively secured to opposite sides of the metalmounting plate79 by means of'rivets 80 I or the like, with theterminals :of the contact elements- 78a to 78f,'inclusive, on each ofthe plates extendingin opposite directions. Alsoincluded as part of the assembled unit ofthe transfer switch 76 are two parallel longitudinallyimovableplates-8121 and 81b preferably of insulating material; which are slidably mounted respectively'on: opposite-sides of: the stationary plates 77a and; 771) by meansofislots 33-Whl6h are slidable on the rivets 84. extending-through the plates 77a, 77band 79, as bestshown iniFig. 3. v iEachtof" the plates 81a and 81b are provided with two bar-likecontact elements 82aand'82b' so. that eachubar-like contact element is normally con tacting adjacent stationary; contact elements, such as 78(17'78b',3.11d5782ir-1178B5-HS best seen in Fig. 2.

When the movable plate is controlled so that it slides torthe leftnasseeniniFig; 2,:the bar-like contact elements 82a1and-82bl on each: of theplatesmove together to the. left 10;. disengage-the bar-like contact elements from the;

stationarywcontacts ':78a:and' 73d and to, engagethe ad;

jacentvstationarycontact elements 78c and'78f: In order by the-dotted: lines the coil'springSS is demountably secured at one end, to a pin 86 extending between the lates film-and 8.1. 2.v balm -the. lower g o ee a P a e-J andctheoppqs te a d; t pr ng. r-

mountably-secured in .an opening-87 providedin thest-ae.

tionary. mounting; plate 79. As shown in Fig. 2, the spring 85 is;i n an extended position because the right,

edge 0i the'ringizl on the; outer sleeve-20 of the plunger 18is inwengagernent with the left edge of the shoulders 88:proyided respectively. on the movable plates 81a and .81b. In addition, to. the toregoing, the, movable. plates 81a and: 81b are respectively provided with transversely aligned cam grooves 89 in which theoppositely disposed cam control lugs 54a and 54b on the switch keeper 54 are inserted.

It should be noted that each of the cam grooves 89 includes a first lower slot 89a, a second upper slot 8% and an interconnecting angular slot 890, so that the keeper 54- will be maintained in the lower position, as illustrated in Fig. 2, while the lugs 54:; and 54b are in the first slot 39a and so that the keeper is raised in a vertical direction under control of the interconnecting slot 890 to the second slot 89b as the movable plates 81a and 81b on the transfer switch 76 are moved to the left. The movement of the movable plates 81a and 81b is under control of the solenoid 30 and the keeper 54, as well as the ring 21 on the outer sleeve 20 of the plunger 18. If the solenoid 30 on the coil spool 31 is energized over an electrical circuit, to be described hereinafter, it creates a magnetic flux field which will attract the switch keeper 54 against the central pole piece 29 on the core 27 to hold the keeper in its lower position, as illustrated in Figs. 2 and 3. This will prevent the plates 81a and 81b from being moved to the left (Fig. 2) under control of the spring 85 even though the ring 21 has moved away from the shoulders 88 on the respective plates 81a and 81b. However, as soon as the electrical circuit for the solenoid 30 is interrupted, the magnetic flux field generated thereby will immediately decay to permit the keeper 54 to be lifted in the cam grooves 89 as the plates 81a and 81b move to the left. There is still another means for preventing the keeper 54 from being lifted by the cam grooves 89 and also to prevent the plates 81a and 8112 from moving to the left (Fig. 2) after the ring 21 has moved away from the shoulders as. This means includes the lug 53d on the rotor 50 (Fig. 3).

More specifically, when the rotor 50 rotates in a clockwise direction (Fig. 3) in response to the energization of the solenoid 30, as will be described hereinafter, the lug 530. on the rotor 50 will rotate to a position immediately above the left shoulder 54d on the keeper 54 and will thereby mechanically prevent the keeper 54 from being lifted or moved upwardly. This action will take place even though the energization circuit for the solenoid 30 is interrupted within an extremely short interval of time after its energization circuit is completed. It will be subsequently seen that the rotor 54 will always be rotated sufficiently in the clockwise direction as viewed in Fig. 3 until the stops 52b and 52d thereon engage the cooperating pole pieces 28b and 28d whenever the solenoid 30 has been energized and rotates the rotor 50 1Q tween the side walls thereof. The slots 90, as seen. in Fig. 2, extend downwardly from the upper edge of the housing 17 a distance which is determined by the extended ends on the metal mounting plates 79 for the transfer switch 76 so that the shoulders 88 on the movable plates 81a and 81b are in a position to engage the end surface on the ring 21 of the outer sleeve 20 on and its shaft 41, an angular distance great enough to enable the cam followers 45 and 46 (Fig. 5) to cooperate with the flat cam surfaces 43 and 44 on the cam 40. Thereafter, the rotor 50 will back away from its advanced rotary position described above, as soon as the solenoid 30 is deenergized, under control of the C-shaped spring 57 in order to withdraw the lug 53d from engagement with the shoulder 54d. Thus, the keeper 54 is retained in its lowermost position while the solenoid 30 is energized and it will also be retained in its lowermost position by means of the lug 53d until the rotor 50 backs away from its advanced rotary position. After both of the above events have occurred, the keeper 54 will be lifted in the manner described previously, as the movable plates 81a and 81b move to the left (Fig. 2). As the movable plates 81a and 81b slide or move to the left with respect to the stationary plates 77a and 77b, the bar-like movable contact elements 82a and 821; on

the respective movable plates will change the circuit conslots 90 formed respectively in the opposite inner. end

walls of the housing 17 and spaced equal distances be the plunger 18. After the transfer switch 76 is thus mounted in the slots in the housing 17, a gasket 91 is placed upon the upper exposed surface of the housing 79, a soft rubber or other resilient like sheet 92 is placed on the upper edge surfaces of the transfer switch 76, the cover 75 is placed thereon with washers 93 and screws 94 utilized to secure the housing in place. As the screws are driven in place, the resilient sheet 92 will be slightly compressed between the upper edges of the stationary plates 77a and 77b and the under surface of the cover 75. Thus, the cover 75 and the resilient sheet 92 will retain the transfer switch 76 in its mounted position in the slots 90 formed in the inner end Walls of the housing 17.

In order to provide the electrical connections to the stationary contact elements 78:: to 78], inclusive, on each of the plates 77a and 77b, and to the winding of the solenoid 30, an opening 95 may be provided in the end Walls of the housing 17 and the cover 75 to permit the cable'96, having appropriate wiring therein, to make the electrical connections with the terminals and solenoid winding noted above and an exterior control panel and power source. Although the opening 95 for the cable 96 has been shown at the right end of the housing 17 and cover 75 as seen in Fig. 2, it will be apparent that this opening may be provided in the left end of the transfer switch housing.

An electrical circuit for controlling one or more of l the mechanisms of the present invention is shown in Fig. 7, and includes the solenoid 30 of the first mechanism and its associated transfer switch 76, a second mechanism is represented by the solenoid 30A and its transfer switch 76A, and the last mechanism in the series is represented by the solenoid 30B. Any number of such mechanisms may be connected in series to successively control the release of successive bombs by a plurality of bombing release shackles 10, as illustrated in Fig. 1.

If it is assumed that a plurality of bomb release shackles 10 and the associated release mechanism 15 are mounted on an aircraft, or the like, and are wired in accordance with Fig. 7, the bombs carried by the respective shackles 10 may be sequentially controlled by successive actuations of the contacts 99, which is either a thumb operated contact mechanism, under control of the pilot of the aircraft, or is a contact which is automatically controlled by' a bomb sight device (not shown). With the release mechanism 15, as illustrated in the drawings in the latched or cooked position and with the electrical wiring connected and arranged as shown in Fig. 7, the closing of the contacts 99 will complete a circuit from the positive terminal by way of the contacts 99, stationary contacts 782 on the plate 775 of the transfer switch 76, movable contact element 82b on the movable plate 81b on the transfer switch 76, contact 78d and the winding of the solenoid 30 to the negative terminal. The positive and negative symbols schematically illustrated represent a source of power. Any voltage may be utilized provided the winding of the solenoid 36 is of appropriate resistance and number of turns, to control the operation of the release mechanism 15. The solenoid 30 will be energized over the above described circuit and will create a magnetic flux which will cause the plunger 18 on the release mechanism 15 to be moved from its latched or cocked position to an unlatched position, but as previously noted, the transfer switch mechanism 76 will delay its movement to the left, as shown in Figs; 2 and 7, until the contacts 99 are again opened to interrupt the energizing circuit for the solenoid 30. With the source 96 (Fig. 2) a circuit is normally completed from the 11 pos ive erm n y w y of con ac s. 812, 221, 4 the lamp 97 and the negative terminal of the source of p wer, for illuminatin e p. 9 1 nd a e at. t e.

' release mechanism 15 isinits latched or cocked position,

s o n s th ontac s. a n e up c t Pet he. u o e i ding of. s en id h eep r. 5st. (F ell Pe mi h mo b pla es laand 2 o be moved to the left under controlof the springtifi, inasu a h p u e f h e han s ha ovedt s. extende u l tc d Os nco ked. pos t o Whea s occurs, the. above. described. circuits for the solenoid '39. and thelamp 97will be interrupted and LQ q ICuitsWill be n parsdto e izingthcsc enoida Acf he secQn lease. ech ni an e amp9i8- ill ei lumi edt d cat at he. r t re ea e. m chanis hasb en tuat d. to release .its bomb. Inother words, acircuit will now be. completedfor illuminating the lamp 98 which includes thenegative terminal, lamp 98;, stationary contacts 78c,

movablecontact Slqwhich is now moved. to the left as viewed in.Eig. 7, stationary contacts 7 8. b and the, ground terminal. Theillurninated condition of. the lamp 98, will indicate that-thebomb. release me hanism. has been. actuated to itsunlatched position. Inasmuch as..the movable contact 82b has been moved to its left position, it. transfers the previously traced circuit including thecontacts 99ffrom the circuit for the first solenoid30. to a. circuit for the second solenoid A. understood that thecontacts 78a, to, 78 inclusive, on the stationary plate 77a. and the-,movable contacts. 82a and. 82]) on themovable plate 81a on each of therelease It, should also be;

mechanisms may beutilized for controlling any other.

desired circuits. (not shown).

The next time the contacts 99 are closed, inasmuch as. thefirst transfer switch 76 has been movedtotransfer thecircuit, the second solenoid 30A will, bcnenergized over a circuit. including the. positive terminal, contacts.

99,782,824'1, 78 the closed. contacts on the transfer.

switch 76A of the second release mechanism and. the.

winding of. the solenoid30A on the second releasetmechanisrntoihe negative terminal. Thus, the secondsolenoid 30A. isenergizcd tocause thesecond release mechanism.

release. mechanism is in. its latched. or cooked. position and after, the corresponding transfer switch 76, 76A, etc. is actuated,.the corresponding lamps..9.3, 98A, etc will e ill mi t d; to indi a at he. or c pon nstrelea e mechanism has moveclto its unlatched or 'uncocked posh. tion. Thps,.the pilot. of the, aircraft, or the likens ill.

have, a visual. signal toindicate the number; of: bomb.-

shackles that have been; actuatedtorelease the associated r b nd ls he-.nsmbewt bomb ha kletm shaa sms that aregstill loaded withan, associated bon;b

h detailed op ra i n f; t e.mech n smtdiscl sed; n. e. dr w n will: nowtbet descri ed. in o junction. with the above electrical circuit as.- illustrated in Figt 7. For

this purpose, it will. be assumed that; the; mechanismof Fig. 2 is in its latched on cocked position, When the;

external contacts 99 are closed, as describedxabove, to. mp e gizinsc cu t fQI' hQ winding of: the solenoid 3th a magnetieflux;field is created-,betwcemthe;

central: pole piece 29,; which is of? onepolarity, and the: spacedrapart circumferential; pole pieces. 4345102281 in:-.

elusive; which will; beoffithe oppositepolar-ityt Since the-rotor 50.havingthe'spaced-apart pole pieces Sla -to 51d is. in;,th.e.magnetic.field of the opposite-polaritieston the pole pieces 28a.to.28d, inclusive, enema. central polepiece.29, the rotor will rotate in a clockwise direction as; seen m.- Fig. 3 to: align-its respective polepieces- 5-14 to 51 1, inclusive, with the stationary pole pieces 28 a,...

the alignment position between therespective pole pieces, the stops 52b and 52d have been provided on the rotor 50 to stop the rotation thereof as soon. as the. above mentioned stops engage the associated pole pieces 28b and 28d. These stops 52b and 52d also provide additional magnetic flux paths to holdthe rotor 50 hits rotated. or trapped position until the circuit of the: coil 30 is interrupted.

The energization of the coil 30in creating the magnetic flux field in the central pole piece 29, attracts the keeper 54 to prevent it from moving upwardly from the position illustrated in Fig. 3. In addition thereto, as soon as the lug 53d on.the rotor 50 moves toa position to overlie the left shoulder 540. on thekeeper 54, it will also prevent the keeper from moving upwardly even though, the,

magnetic flux field no longer attracts the keeper 54 to,

shaft. 41 in a clockwise direction as,seen. in Fig. 5 of the drawings. Normally, in its illustrated position, the

cam.40. is arranged. so thatthe oppositely disposed high points on. the surface thereof retain the. oppositely dis.-

posed latch members 33 and 34 .in .theposition. shown, in .F-ig. 5 so that the cooperating angular surfaces 38 on.

the latches33 and 34 and the inner circumferential wall. of the plunger 18 will prevent the plunger from being forced to the left as seen in. Fig. 2 under control of. the. heavy compression spring 23. As the rotor 50 begins to rotate and moves the shaft 41, the high points on the.

cam 40 will be rotated a. few degrees until} the angular cam follower surfaces45 and 46 on the respective latch members 33: and 34. engage the oppositely disposed flat cam surfaces 43 and 440m the cam- 40. Although themagnetic. flux field. created by the energization of the solenoid 30 will cause the rotor' 50 to rotate from its. normal position to. its advance rotary position with the stops 52b and 52 d thereon into engagement with the,

pole pieces. 28b and 28d, it should be understood that.

this rotary'action is considerably enhanced bythe action of the cam. follower surfaces 45 and 46 against the fiat.

cam surfaces 43 and 44 because the latch members 33.

and Marc being; forced toward each other under control of thepressure exerted by the heavy compression spring,

23 against the angular surfaces 38 on the respective latchmembers 33 and 34. The. outward pressure thus exerted-will compress the latch members 33 and; 34 to-. ward each other and the cooperating cam surfaces-noted above will further rotate the cam 40, its. shaft, 41 and the rotor 50: in the clockwise direction as seenin Fig. 5 even though the energizing circuit for the, solenoid; 30, as be n-int up e The angle of the angular, surface 38' is approximately five degrees so thatitis apparent that as 'longas the latch members 33 and34are held. in their outward positions. by thehigh surfaces on the cam 40,. the plunger, 18; will be prevented from moving to its extended position, but as soon as the cam 40; rotates sufficiently: to. release the outward pressure between the latches 33-, and 34', then the.

compressed spring. 23 will; force the plunger 1.8;:to the left as viewed in.- Fig.3 2. against; the. angular: surface 38: to;

ur h r r duce the. distance betweenthe .two. latch mem:

bers 33. and; 34.- Also,.the action .of-[pressing' the latch members toward .eachother cause the, cam surfaces 45 and 46 .to .act against the. flat cam surfaces. 43. and144 to further rotate the cam 40 and the shaft 41. As soon as pressed spring 2;3-will force the'plunger 18' outwardly to on the housing 16 was sometimes badly distorted. However, in the present invention, the felt ring 25 and the split steel ring 24.functin as a brake mechanism when the angular circumferential surface 22 on the ring 21 of the outer sleeve of the plunger 18 engages the cooperat -ing angular surface 24b on the split ring 24. The braking action of the ring 24 and its felt washer 25 is brought about by the angular surface 24b thereon tending to further expand the ring 24 in its groove 24a. The braking thus obtained by the rings 24 and 25 in cooperation with the groove 24a and the angular surfaces 22 and 24b, will quickly, but without shock, bring the plunger 18 to a stop position without putting any objectionable strain on the shoulder 26 on the housing 16. In fact, the housing may now be made of aluminum whereas in prior devices it was necessary to make it of relatively hard steel. It should be noted that as soon as the ring 21 on the plunger 18 moves away from the shoulders 88 on the respective movable plates 81a and 81b on the transfer switch 76, the spring 85 will normally tend to move the movable plates from the right-hand positions to the lefthand positions in order to transfer the electrical circuits through the contacts thereon. However, the movement of the plates noted above can not take place until the energizing circuit for the coil has been interrupted, for example, by the contacts 99 or if the circuit has previously been interrupted, the plates can not be moved until the keeper 54 is released by the lug 53d on the rotor 50.

It will now be assumed that the solenoid coil 30 is still in its energized condition and, accordingly, the keeper 54 will be held against the central pole piece 29 by magnetic attraction and also by the lug 53d which is held in position in engagement with the shoulder 54d on the keeper 54, as long as the rotor 50 has its pole pieces 51a to $10!, inclusive, in alignment with the stator pole pieces 28a to 2811, inclusive. If the circuit for the solenoid 30 is now interrupted by the opening of the contacts 99, the magnetic flux field created by the solenoid 30 will immediately decay and will permit the spring 57 to rotate the rotor 50 in a counter-clockwise direction, as seen in Fig. 3. However, the spring 57 can not fully restore the rotor 50 due to the fact that the flat surfaces 43 and 44 on the cam 40 will engage the co-acting surfaces 45 and 46 on the latch members 33 and 34. Although these cam surfaces cooperate in attempting to move the latch members outwardly to assist the latch spring 37 to the normal latching positions, the outward movement is retarded by the wall of the slots 19a formed in the inner sleeve 19 of the plunger 18. The counterclockwise rotation of the rotor 50 is suflicient, however, to withdraw the lug 53d from the locking position above the shoulder 54d on the keeper 54. Also, the decay of the magnetic flux field upon the deenergization of the solenoid 30 will release the keeper 54 so that it can be raised in its cooperating slot in the spool head of the coil spool 31.

More specifically, since the keeper 54 is now fully released and the ring 21 on the sleeve 20 of the plunger 18 has been withdrawn from the shoulders 88 on the movable plates 81a and 81b, the spring 85 will now function to move the plates 81a and 81b in their slots 83 to the left as viewed in Fig. 2 to transfer the circuits through the contacts 78a to 78 inclusive, and the contacts 82a and 82b on the respective movable plates 81b and 81a in the manner previously described. As the plates 81a and 81b are moved to the. left, the cam con- 14 trol lugs 54a and 54b on the keeper 54 will ride in the slots 89 from the lower slot 89a up the inner connecting angular slot 890 to the upper slot 89b thus raising the keeper 54 in a vertical direction. Thus, the actual transferring of the circuits through the contacts of the transfer switch 76 can nottake place until the circuit to the solenoid 30 has been interrupted by the external contacts 99, because the keeper 54 is held in its lower-most position. On the other hand, if the solenoid energizing circuit is interrupted to eliminate the magnetic flux field, the keeper 54 will instead be held in its lower-most position by the lug 53d on the rotor 50. The counter-clockwise rotation of the rotor 50 to withdraw the lug 53d from the shoulder 54d on the keeper will occur as a result of the decay of the magnetic flux upon the deenergization of the solenoid 30 or, if the circuit has already been interrupted, then the keeper 54 will be released by the spring 57 partially restoring the rotor 50 in its counterclockwise direction sufficiently to withdraw the lug 53d from the shoulder 54d. As is previously described in connection with the circuit arrangement illustrated in Fig. 7, the next closure of the contacts 99 will now complete the circuit for the second release mechanism solenoid 30A inasmuch as the transfer switch 76 of the first release mechanism has been actuated.

In order to fully restore the rotor 50 to its original position, it is now necessary to return the plunger 18 to the position illustrated in Fig. 2. This may be done by an inwardly directed axial force exerted manually, or otherwise, on the outer left-hand end of the plunger 18. As the plunger 18 is forced inwardly, the spring 23 is compressed and when the angular surface 38 on the plunger 18 reaches the cooperating angular surface on the respeetive latch members 33 and 34, the latch spring 37 will move the latch members 33 and 34 away from each other to latch the plunger 18 in the illustrated position. As soon as the latch members are moved away from each other to the latching position, the C-shaped spring 57 on the rotor 50 will rotate the rotor in a counter-clockwise direction to the position illustrated in Fig. 3. It being understood that the high points on the cam 40 will hold the latch members 33 and 34 in their expanded positions to mechanically hold the plunger 18 in its latched position. The external inwardly directed axial force may now be removed inasmuch as the plunger is restored to its latched position.

Incident to the movement of the plunger 18 toward its latched position, the ring 21 on the outer sleeve 20 on the plunger 18 will engage the shoulders 88 on the respective movable plates 81a and 81b and will move the respective plates, against the tension of the spring 85, in the slots 83 to the right as shown in Fig. 2, to the illustrated position. During this movement, the cam control lugs 54a and 54b on the keeper 54 will be controlled by the cam grooves 89 to move the keeper 54 downwardly to the position illustrated in Fig. 3. All of the parts comprising the release mechanism 15 are now restored to their latched positions so that they may again be controlled to move to the unlatched position under control of the compression spring 23 when the mechanism is again released.

In the previous description, the release of the mechanism was accomplished by completing an electrical circuit to the winding of the solenoid 30. However, it is necessary in the event of circuit failure to provide some means whereby the mechanism may be otherwise released. For example, if the electrical circuit fails and can not control the release of the mechanism 15, it is advisable to provide an alternative release control so that the bombs may be disposed of without endangering the pilot and other personnel on the ground or the aircraft carrier when the plane returns to its base. The mechanism of the present invention is provided with a positive manual release device which accomplishes the same control of the release mechanism as though the solenoid thereof is stood" thatthe auxiliary controlpof the release could be accomplished by': many other means, including, for ex ample an explosivebellows, a bimetallic strip, a fuseable link, or the like.

InFig. ,2 the pins 66 shownat the right and extend outwardly a short distanceinrthe trip housing60 and they'a-re respectively :secured .to oppositely extending arms on the triparm 65. Since the trip arm is rigidly secured to the rotatable trip-member 59, the manual rotation of the trip arm 65 will cause the rotation ofthe rotor-50 in. substantially the same manner as though itisxrotated by the magnetic fieldcreated by the energized solenoid -30. The pins 66-onthe triparm 65 may, of course, tbeusedrto turn thetrip arm 65 by the thumb and finger of an operator: orthey maybe connected by means of a flexible cable to; a position-that: is readily available to the pilot or other member of the airplane. When the trip; arm is: rotated in a -counter-clockwise direction, as-

seen in Fig. 6, clockwise direction as seen in Fig. -4,.the trip member 59 will engage the studs 62 on .the-rotorl'50 and will therebycause rotationof the rotor intazclock wise-direction -as seen in- Fig; 3. its-shaft 41imayi be :manually rotated approximately 35 degrees but-actuallyit'isnot necessary to manually rotatethe rotor 50 more,than-aprfiroxirhately 12 degrees because as soonasthe'latter amount of rotationtakes. place, the cam'surfaces 43'to 4 6, in'clusive,-Will cooperate in'the manner previously-described to, thereafter control-further rotationof-the rotor 50-. In other-words, the pressure exerted upon the11atch:members33 and34 by the angular surface 38 on the plunger 118will force thelatchmembers toward-eachzothers-and against thetcam surfaces 43 to 46 to complete the rotationxof-tthe shaft 41' and rotor Themanually actuated trip arm' 65 may be released as soon as llxhas'bfifil'lf rotated approximately 12 degrees and the C-shaped spring 61 will immediately function to restore thetri'p member'59 and trip arm- 65- to their initial positions, asillustrated'iniFigsL 4 and6. Further opera tion of the releaseunechanism -15 as the result of themomentary actuation of the trip arm 65 is exactly the same as has been :previouslydescribed in connection with the electrical vactuation of the release mechanism 15.

The-mechanismis substantially sealed by means of the' sealing rings 64-and"71 which :rnaylbe rubber or silicon rings-:having-a cylindricalcross-section and they act as cushions between t the trip housing :60 and the main body of the,:cylindrical housingtl6 and between the trip housingt6tl'1and the'sshaftlon the' trip-'member'59: "In this connection, itshouldbe' -nbtetl-thatthe feltring 25 'pro' vided-betwcen therouter'sleeve' 20' of'the plunger'i19"and the cylindrical housing 16 also acts as a sealer to prevent moisture, dirt; etc, from entering-the interior of the mechanism;

The release -mechanism of the present-invention is somewhat smaller andilighter'in' weight than prior-known I release mechanisms and-iit'is capable of-stor'ing a greater" amount of "releasable-energy"than the prior devices;- lt

will beunderstood 'thabth v mount of store'd energy may A be I either increased "or-* decreased dependingupoii the amountof worki'that is requiredt Fnrtherrii'ore; the eseut-mechanism' williwithstand all of the severe shock tests and fatigue atestsr that have :hereto'fore rendered known V release mechanisms-:ino1ierativeand-issufiiciently' shock proof-to prevent -inadvertent release iofithe' mechanism underv severe 'gshockconditions;

Thus, the rotor 50iand' 16 While there hasbeen described whatgis at present considerd to be the, referred 'eriibo'dimen'tofthe invention, it will be understood that various modifications be made therein whichfall within the true spirit and scope of "the invention. I o

What is clairried is:

l. A shockproof energy storing and release mechanism comprising, a" housing having a' hollow longitudinally movable, plunger, locking" means supported within" theinterior of said hollow plun'g'e'i', said locking means havf ingla locking position in engagement with SQD IHfGIIOI surface ofsaidfplun geri' for etaipin said plunger-hr cocked ener y s aring position ana having an unlocking position releasing said; plunger from said 'cocked position,a rotatable cam cooperating with said-locking means" having. a "first position holdingsaid locking means in said" locking position and movable to a" second position to release said locking means'arid'permitmovenienf thereof from its said T locking position to' said unlocking"v position, rriean'ssel'ectively controllable to rotate:- said cam froniv said'first position to:said 'secondLpositioh" and may res i m 'aj t t t i gb dfl-t tie' eif ective in response to saidrelea s'e of said lockingme'an's for controlling: saia mage to quickly move said locking} means toiits said-unlocking position as said spring means expends its stored energy longitudinally moving said plungerfromsaid cocked position. 1 k U 2, flThe mechanisrnrsetforth in] claim -1, whereii1 said locking means includes a plurality of circumferentially spaced-apart latchimemb ersflatch spring means" bias said latch .membersl-ou twardly to said". locking position, and wherein said: lockingrneans ismovedjfroiii said locking -positionto said unlock-ing vposition against the biasing force of ssaidla tchhspring means. I I v 3. The mechanism .set forthinicla imj 1, including a solenoid supported in. said i housing concentric with said cam rotating; means .and longitudinally disposed with respect tosaid.p lunger, a nd a rotor secured to said m1 rotating means actuatedby energi za tion of said solenoid to selectively controlsaid carn rotating means in order? to' rotate said cam-"from said first position to said s eco nd p t n: v v

4, The' mechanism-set forth in clairri 1, including" a rotatable trip arm :supported in said housing concentric with-said cam rotatingmeans and glongitudinally disposed with respect tosaid plunger, and means-secured to said: rotatabletriptarm etfective inresponse-to rotation of said'trip arm to selectively control saidzcarrr rotating meansin order-.to-rotate saidcamfrom said first posi- =tion-to,sa-idsecond .position. I o v '5. The mechanism set forth in claim '1, including-a solenoid in said housingv concentric with said cam 'rotating-tmeans and longitudinally disposed with respect to' said plunger, -a rotatable trip-armsupported in said hous-j ingiconcentri'c with said cam rotating means and "longitudinally disposed with respect'to saidplungerya rotor secured"to'said;:cam rotatingmeans actuated either by energizationiof said wsolenoid .or by rotation of said trip armwto-selectivelyucontrol-rsaid cam rotating-means in order 1 torotate said cam from said 'firstiposition to said secondposition:

6. Thexmechanismkset forthin'claim '3, including-a central-:co'resupportingsaid solenoid thereon'to form' a first t central ipole piece and having a plurality of arms thereon extending parallel to said core and forming-' 1 plurality of :cireumferentially spaced apart second "pole piecesiso tHatEenergiZatiOnofs said solenoid-:ere'ates xii-mag netic flux-'ifield'ofra first pol'arity at sai'd'ffirst:central pole' piece ar'idra'magneticifluxifield'ofa second pol'arity attsaid second ipo'le rpiece's, and wherein Isai'd iroto'r'. is positioned withmespect to'saidifirStpQIe pieceandsa'id ise'c'ond pole PlECES-"ztO rotate-2a predtermined angle "ofrotation inresponseito'ss-aidemagnetic flux' fields of sai'd first and second-polarities? 7. Thei me'chanism isetiforthin claim 6, wherein said 17 1 central core pivotally supports said locking means for pivotal movement between said locking and said unlock: ing positions and guides said plunger during longitudinal movement thereof from said cocked position.

8. The release mechanism set forth in claim 1, including a central core, wherein said plunger includes an inner sleeve slidably mounting said plunger for longitudinal movement on said core and an outer sleeve circumferentially spaced-part from said inner sleeve to form therebetween a cylindrical cavity to house said energy storing spring means therein.

9. The release mechanism set forth. in claim 8, wherein said outer sleeve on said plunger forms a cylindrical bearing for slidably mounting said plunger for longitudinal movement with respect to said housing, a stop ring formed around the periphery of one :end of said outer sleeve, stop means formed in one end of said housing to terminate said longitudinal movement of said plunger from said cocked position, said stop means in said housing including an expandable ring supported between said housing and said outer sleeve in a position to be engagedby said stop ring, said expandable ring acting as a friction brake in response to engagement thereof by said stop ring during said longitudinal movement of said plunger from said cocked position by expanding outwardly against the inner surface of said housing to quickly terminate said longitudinal movement of said plunger with respect to said housing.

19, The release mechanism set forth in claim 8, wherein said housing includes an end shoulder forming a collar surrounding said outer sleeve on said plunger, an expaudable ring normally surrounding said outer sleeve of said plunger and restrained against longitudinal movement with respect to said plunger by a circumferential groove formed in the inner surface of said housing adjacent said collar, an outwardly protruding stop ring circumferentially formed around the peripheral surface of said outer sleeve adjacent one end thereof, and surfaces on said expandable ring and said stop ring cooperating in response to engagement thereot as a result of said longitudinal movement of said plunger from said cocked po t n for expanding d xpandab e ring outwa dly into said groove so that said expandable ring co-acts with said housing as a friction brake to terminate said longitudinal movement of said plunger and thereby substantially preventing the shock of stopping said movement of said plunger from being transmitted to said collar on said housing.

11. An energy storing and release mechanism comprising, a spring loaded hollow plunger, pivoted latch niem bers supported within the interior of said plunger biased outwardly to a latching position to retain said plunger in latched position against the tension of said spring and movable to an unlatching position against said bias, a cam positioned between said latch members and movable from a first position to a second position, said cam in said first position mechanically holding said latch members in said latching position and movable to a second position to permit said latch members to be pivoted toward an unlatched position, a shaft concentric with said plunger secured to said cam, and means for rotating said shaft a predetermined distance to move said cam from said first position to said second position to unlatch said latch members, said plunger in response to said movement of said cam from said first position being released from said latched position to move toward an unlatched position and simultaneously moves said biased pivoted latch members toward each other to an unlatching position.

12. An energy storing and release mechanism comprising, a spring loaded hollow plunger, pivoted latch members supported within said plunger and biased outwardly to a latching position to retain said plunger in latched position against the tension of said spring and movable to an unlatched position against said bias, a cam positioned between said latch members and movable from a first position through a second position to a third position, said cam in said first position mechanically holding said latch members in said Futching position and movable to a second position to permit said latch members to be pivoted toward said unlatched positions, a shaft concentric with said plunger secured at one end to said cam, a rotor secured to the opposite end of said shaft, and means for rotating said rotor a first distance to move said cam from said first position to said second position to unlatch said plunger, said plunger in response to said movement of said cam to said second position being released from said latched position moves to an unlatched position and simultaneously reacts to move said biased pivoted latch members toward each other to move said cam from said second position to said third position.

13. An energy storing and release mechanism comprising, a housing, a tubular plunger having a closed end and an open end longitudinally movable from a cocked position in said housing to a predetermined extended uncocked position, locking means supported within said plunger adjacent said closed end thereof for retaining said plunger in said cocked position, a coil winding supported in said housing longitudinally of the open end of said plunger energizable by an electrical impulse to generate a magnetic flux field, a rotor positioned coaxial with said plunger and longitudinally of said open end thereof and rotatably actuatedby said magnetic flux field for releasing said locking means from said locked position, a load spring in said plunger efiective in response to said release of said locking means from said locking position to move said plunger longitudinally with respect to said housing from said cocked position toward said predetermined extended uncocked position, and brake means cooperating between said plunger and said housing for frictionally retarding said longitudinal movement just prior to said plunger reaching said extend-ed uncocked position. I 7

14. The mechanism set forth in claim 13, including a transfer switch mounted in said housing comprising a first stationary plate supporting a plurality of contacts, a movable second plate supporting a plurality of contacts longi udinally movable with respect to said first plate from a first position to a second position to switch circuits through different sets of stationary contacts on said first plate, means on said plunger in said cocked position mechanically retaining said second plate in said first position until said plunger is released from said cocked position, a keeper carried by said second plate normally in a first position and movable to a second position in response to longitudinal movement of said second plate from its first position to its second position, said keeper in response to said generated magnetic flux field being held in its normal first position to preventing longitudinal movement of said movgale second plate even though said plunger and said means thereon is released from said cocked position by said rotation of said rotor, and said keeper permitting longitudinal movement of said second plate from its first position to its second position as soon as magnetic flux field decays in response to the termination of said eleotrical impulse.

15. The mechanism set forth in claim 14, wherein said rotor is rotated a predetermined angle of rotation in response to said magnetic flux field generated by energization of said coil winding and remains in said predetermined rotary position until said magnetic flux field decays in response to deenergization of said coil winding, means for mechanically rotating said rotor to said predetermined position in the event said deenergization of said coil winding occurs before said rotor reaches said predetermined rotary position, and means on said rotor for holding said keeper in said normal first position as long as said rotor remains in said predetermined rotary position, and a restoring spring for withdrawing said rotor from said predetermined position to release said .19 keeper to permit movement thereof to said second position.

16. The mechanism set forth in claim 15, wherein said rotor restoring spring withdraws said rotor from said predetermined rotary position to release said keeper for movement from said normal first position to said second position either in response to said decay of said magnetic flux field by deenergization of said coil winding or in response to said mechanical rotation of said rotor into said predetermined rotary position depending upon the event last to occur.

17. An energy storing and energy release mechanism, comprising, a housing, a spring in said housing having an energy storing position and an energy release position, a longitudinally extending tubular plunger mounted for longitudinal movement in said housing between a first position retaining saidspring in said energy storing position and a second position releasing said spring to expend its stored energy, a shoulder carried by said plunger, a latch disposed within said plunger and selectively movable into and out of latching engagement with said shoulder, a cam having a set position holding said latch in latching engagement with said shoulder and a release position accommodating movement of said latch out of latching engagement with said shoulder, means for selectively moving said cam from its set position into its release position, said latch being of the quick-release type so' that it is immediately moved out of latching engagement with said shoulder in response to only slight movement of said cam from its set position toward its release position, said movement of said latch out of said latching engagement with said shoulder being controlled by said spring moving said plunger from said first position toward said second position.

18. An energy storing and energy release mechanism comprising, a housing, a spring in said housing having an energy storing position and an energy release position, a longitudinally extending tubular plunger mounted for longitudinal movement in said housing between a first position retaining said spring in said energy storing position and a second position releasing said spring to expend its stored energy, a shoulder carried by said plunger, a latch disposed within said plunger and selectively movable into and out of latching engagement with said shoulder, a cam having a set position holding said latch in latching engagement with said shoulder and v a release position accommodating movement of said latch out of latching engagement with said shoulder, means for selectively moving said cam from its set position into its release position, said latch of the quick-release type'includes a first tapered latch surface normally engaging a second tapered latch surface forming said shoulder carried by said plunger so that said first latch surface is immediately moved out of complete engagement with said second latch surface in response to only slight movement of said cam from its set position toward its release position, said movement of said latch out of said latching engagement with said shoulder being controlled by said spring moving said plunger from said first position toward said second position.

19. The mechanism set forth in claim 18, wherein said latch surfaces taper in the direction of longitudinal movement of said plunger at an acute angle to the longitudinal axis of said plunger.

20. The mechanism set forth in claim 19, wherein said acute angle is about degrees.

21. A shockproof energy storing and release mechanism comprising, a housing having a longitudinally movable plunger, locking means supported within said plunger normally having a locking position to retain said plunger in a cocked energy storing position and releasable to an unlocking position to release said plunger from said cocked position in said housing, and a rotatable cam cooperating with said locking means having a first position to hold said locking means in said locking position and movable to a second position to release said locking means so that it may be moved from said locking position to said unlocking position.-

References Cited in the file of this patent UNITED STATES PATENTS 2,362,210 Markey Nov. 7, 1944 2,416,028 Sloan Feb. 18, 1947 2,473,597 Leland June 21, 1949 2,535,095 Schwartz et al. Dec. 26, 1950 

